US5251733A - Transmission control with limp-home function - Google Patents

Transmission control with limp-home function Download PDF

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Publication number
US5251733A
US5251733A US07/923,701 US92370192A US5251733A US 5251733 A US5251733 A US 5251733A US 92370192 A US92370192 A US 92370192A US 5251733 A US5251733 A US 5251733A
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United States
Prior art keywords
limp
home
transmission
shift lever
gear
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Expired - Lifetime
Application number
US07/923,701
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English (en)
Inventor
Peter L. Falck
Charles W. Formwalt, Jr.
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Deere and Co
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Deere and Co
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Filing date
Publication date
Application filed by Deere and Co filed Critical Deere and Co
Priority to US07/923,701 priority Critical patent/US5251733A/en
Assigned to DEERE & COMPANY reassignment DEERE & COMPANY ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: FALCK, PETER L., FORMWALT, CHARLES W., JR.
Priority to CA002099156A priority patent/CA2099156C/en
Priority to JP16691093A priority patent/JP3502416B2/ja
Priority to EP93111339A priority patent/EP0581124B1/de
Priority to DE59307449T priority patent/DE59307449D1/de
Application granted granted Critical
Publication of US5251733A publication Critical patent/US5251733A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16H—GEARING
    • F16H61/00—Control functions within control units of change-speed- or reversing-gearings for conveying rotary motion ; Control of exclusively fluid gearing, friction gearing, gearings with endless flexible members or other particular types of gearing
    • F16H61/16—Inhibiting or initiating shift during unfavourable conditions, e.g. preventing forward reverse shift at high vehicle speed, preventing engine over speed
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16H—GEARING
    • F16H61/00—Control functions within control units of change-speed- or reversing-gearings for conveying rotary motion ; Control of exclusively fluid gearing, friction gearing, gearings with endless flexible members or other particular types of gearing
    • F16H61/02—Control functions within control units of change-speed- or reversing-gearings for conveying rotary motion ; Control of exclusively fluid gearing, friction gearing, gearings with endless flexible members or other particular types of gearing characterised by the signals used
    • F16H61/0202—Control functions within control units of change-speed- or reversing-gearings for conveying rotary motion ; Control of exclusively fluid gearing, friction gearing, gearings with endless flexible members or other particular types of gearing characterised by the signals used the signals being electric
    • F16H61/0248—Control units where shifting is directly initiated by the driver, e.g. semi-automatic transmissions
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16H—GEARING
    • F16H61/00—Control functions within control units of change-speed- or reversing-gearings for conveying rotary motion ; Control of exclusively fluid gearing, friction gearing, gearings with endless flexible members or other particular types of gearing
    • F16H61/12—Detecting malfunction or potential malfunction, e.g. fail safe; Circumventing or fixing failures
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60W—CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
    • B60W2510/00—Input parameters relating to a particular sub-units
    • B60W2510/02—Clutches
    • B60W2510/0208—Clutch engagement state, e.g. engaged or disengaged
    • B60W2510/0225—Clutch actuator position
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60W—CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
    • B60W2540/00—Input parameters relating to occupants
    • B60W2540/14—Clutch pedal position
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16H—GEARING
    • F16H61/00—Control functions within control units of change-speed- or reversing-gearings for conveying rotary motion ; Control of exclusively fluid gearing, friction gearing, gearings with endless flexible members or other particular types of gearing
    • F16H61/12—Detecting malfunction or potential malfunction, e.g. fail safe; Circumventing or fixing failures
    • F16H2061/1232—Bringing the control into a predefined state, e.g. giving priority to particular actuators or gear ratios
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16H—GEARING
    • F16H61/00—Control functions within control units of change-speed- or reversing-gearings for conveying rotary motion ; Control of exclusively fluid gearing, friction gearing, gearings with endless flexible members or other particular types of gearing
    • F16H61/12—Detecting malfunction or potential malfunction, e.g. fail safe; Circumventing or fixing failures
    • F16H2061/1256—Detecting malfunction or potential malfunction, e.g. fail safe; Circumventing or fixing failures characterised by the parts or units where malfunctioning was assumed or detected
    • F16H2061/126—Detecting malfunction or potential malfunction, e.g. fail safe; Circumventing or fixing failures characterised by the parts or units where malfunctioning was assumed or detected the failing part is the controller
    • F16H2061/1268—Electric parts of the controller, e.g. a defect solenoid, wiring or microprocessor
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16H—GEARING
    • F16H61/00—Control functions within control units of change-speed- or reversing-gearings for conveying rotary motion ; Control of exclusively fluid gearing, friction gearing, gearings with endless flexible members or other particular types of gearing
    • F16H61/12—Detecting malfunction or potential malfunction, e.g. fail safe; Circumventing or fixing failures
    • F16H2061/1256—Detecting malfunction or potential malfunction, e.g. fail safe; Circumventing or fixing failures characterised by the parts or units where malfunctioning was assumed or detected
    • F16H2061/1284—Detecting malfunction or potential malfunction, e.g. fail safe; Circumventing or fixing failures characterised by the parts or units where malfunctioning was assumed or detected the failing part is a sensor
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16H—GEARING
    • F16H59/00—Control inputs to control units of change-speed-, or reversing-gearings for conveying rotary motion
    • F16H59/36—Inputs being a function of speed
    • F16H59/38—Inputs being a function of speed of gearing elements
    • F16H59/40—Output shaft speed
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16H—GEARING
    • F16H59/00—Control inputs to control units of change-speed-, or reversing-gearings for conveying rotary motion
    • F16H59/36—Inputs being a function of speed
    • F16H59/38—Inputs being a function of speed of gearing elements
    • F16H59/42—Input shaft speed
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16H—GEARING
    • F16H59/00—Control inputs to control units of change-speed-, or reversing-gearings for conveying rotary motion
    • F16H59/50—Inputs being a function of the status of the machine, e.g. position of doors or safety belts
    • F16H59/56—Inputs being a function of the status of the machine, e.g. position of doors or safety belts dependent on signals from the main clutch
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16H—GEARING
    • F16H61/00—Control functions within control units of change-speed- or reversing-gearings for conveying rotary motion ; Control of exclusively fluid gearing, friction gearing, gearings with endless flexible members or other particular types of gearing
    • F16H61/68—Control functions within control units of change-speed- or reversing-gearings for conveying rotary motion ; Control of exclusively fluid gearing, friction gearing, gearings with endless flexible members or other particular types of gearing specially adapted for stepped gearings
    • F16H61/684—Control functions within control units of change-speed- or reversing-gearings for conveying rotary motion ; Control of exclusively fluid gearing, friction gearing, gearings with endless flexible members or other particular types of gearing specially adapted for stepped gearings without interruption of drive
    • F16H61/686—Control functions within control units of change-speed- or reversing-gearings for conveying rotary motion ; Control of exclusively fluid gearing, friction gearing, gearings with endless flexible members or other particular types of gearing specially adapted for stepped gearings without interruption of drive with orbital gears

Definitions

  • This invention relates to a vehicle transmission control system, in particular an electronic control system for a powershift transmission having a limp-home capability.
  • an electrohydraulically controlled power shift transmission proper function is dependent on several components. These components include the operator controls (e.g. shift lever and associated parts), the microcomputer-based transmission controller, the electrohydraulic valves, the wiring and the transmission elements. If any of these were to fail, the operator may lose at least part of the normal transmission function. In a worst case, the transmission would no longer carry torque and the tractor would not move. Loss of tractor motion is a major failure, so it is desirable to have a transmission system with a "limp-home" capability wherein limited tractor motion is provided in case of failures of the PST system with only the components which are normally sold as part of the tractor. In other words, the tractor must move under its own power with whatever function of the transmission is available.
  • a known transmission for a production agricultural tractor provides a limp-home function by disconnecting a wiring harness from the transmission controller and then connecting the two harness connectors together. It is believed that, with this known system, a clutch switch is normally closed which enables the limp-home function. Therefore, the clutch pedal need not be used when operating in the limp-home mode. However, the clutch pedal as well as the shift lever can be used to stop vehicle motion. When the clutch pedal is fully depressed, the clutch switch opens, thereby dropping power to a transmission control valve solenoid which is required for motion in both first forward gear and first reverse gear. Non-modulated engagement will occur when the shift lever is moved into gear with the clutch pedal released or when the clutch pedal is released with the shift lever in gear.
  • Gear engagement with this system cannot be modulated by operation of the clutch, and therefore generates a jerk to the operator which is worse when engagement occurs at higher engine speeds.
  • this known system only first forward and reverse gears are available in the limp-home mode. As a result, the tractor is unusable for continued work. It would be desirable to have a limp-home function which would permit modulated engagement and which would enable a gear which is in the working range.
  • Another known production powershift transmission also has a limp-home function. This is obtained by swapping certain connectors and then operating a momentary switch which allows one forward and one reverse gear.
  • This limp-home circuit requires that the operator manually maintain the switch actuated in order to maintain motion. If the switch is released, the transmission disengages.
  • This limp-home circuit is intended only for moving the tractor onto a vehicle or to a repair area and is not intended for continued working. It bypasses all electronic functions, including the shift quadrant and any motion preventive features, such as start-in-gear protection, as well as the transmission controller. This system would also allow gear engagement if the limp-home switch had failed or had been defeated such that it was stuck in the forward or reverse position.
  • An object of the present invention is to provide a limp-home function for a control system for a powershift transmission which permits modulated gear engagement.
  • Another object of the invention is to provide such a limp-home function method which does not defeat start-in-gear protection.
  • a control system for a vehicle powershift transmission includes a set of electrical connectors which, in a normal mode, permit electrical power to be transmitted to microprocessor-controlled valve drivers for the transmission clutch control valves. These connectors may be swapped, in a limp-home mode, to permit power to be transmitted directly to the transmission clutch control valves.
  • a start-in-gear protection circuit including a pair of relays and switches coupled to the shift lever prevents the vehicle from being started up with a gear engaged.
  • a limp-home relay and a clutch disengaged switch prevents gear engagement until the operator has depressed and then released the clutch pedal, and the clutch pedal may be operated to modulate and control gear engagement.
  • FIG. 1 is a schematic block diagram of a microprocessor-based transmission control system to which the present invention is applicable.
  • FIG. 2 is a schematic representation of a transmission to which the present invention is applicable.
  • FIG. 3 illustrates in greater detail a portion of the transmission of FIG. 2.
  • FIG. 4a shows the arrangement of FIGS. 4b-4f.
  • FIGS. 4b-4f are combined to show a circuit diagram of the control circuit of the present invention.
  • a vehicle power train includes an engine 10 which drives a power shift transmission 12, which has an output shaft 13, which, via a conventional tow disconnect mechanism 14, drives an output drive shaft 16 which is connected to drive wheels (not shown).
  • the power shift transmission 12 includes a transmission 18 which is operated by a set of pressure operated control elements or clutches 20 which are controlled by a corresponding set of solenoid operated proportional control valves 22.
  • the transmission 18 may be a transmission such as described in U.S. Pat. No. 5,011,465, issued Apr. 30, 1991 to Jeffries et al., and assigned to the assignee of this application.
  • the valves 22 may be two-stage electrohydraulic valves as described in U.S. Pat. No. 4,741,364, issued May 3, 1988 to Stoss et al. and assigned to applicant's assignee.
  • the power shift transmission control system includes a transmission control unit 30, a chassis computer 32 and a dash display 34.
  • the transmission control unit 30 and the chassis computer 32 are preferably microprocessor-based electronic control units. Manual control is achieved via a gearshift lever 36.
  • a gearshift switches and encoder unit 38 provides signals representing the position of the lever 36 to the transmission control unit 30.
  • a clutch engagement switch 40 and a clutch disengagement switch S4 provide signals representing the position of a clutch pedal 44.
  • the chassis computer 32 receives signals from an engine speed sensor 46.
  • the chassis computer 32 also receives signals from a ground speed sensor 48 and a transmission oil temperature sensor 50.
  • the chassis computer sends information from these sensors to the transmission control unit 30 and to display 34.
  • the transmission control unit 30 includes a commercially available microprocessor M which supplies control signals to a set of valve drivers 24 which provide variable duty cycle pulse-width-modulated voltage control signals to the valves 22.
  • the transmission control unit 30 and the valve drivers 24 will generate such control signals as a function of various sensed and operator determined inputs in order to achieve a desired pressure in the clutches and to thereby control the shifting of the transmission 12 in a desired manner.
  • the present invention is not concerned with the control of the shifting of the transmission 12, the transmission 12 itself, or the valves 22, since the present invention is concerned only with the limp-home aspect of the control circuit shown in FIGS. 4b-4f.
  • the control elements of transmission 12 include a set of brake elements B1, B2, B3, B4 and B5, and a set of clutch elements C1, C2, C3, and CLO.
  • the input shaft 52 is connected by splines 54 to the clutch drum 56 of clutch C1 and of clutch C2 (not shown in FIG. 3).
  • the drum 56 in turn is splined to the clutch separators 58 of clutch C1.
  • the clutch disks 60 of clutch C1 are splined to the clutch hub 62 of clutch C1.
  • the clutch hub 62 is splined to a first intermediate shaft 64.
  • the first clutch C1 is provided with a piston 66 for activating the clutch C1 by compressing the clutch separators and disks 58, 60.
  • a spring 68 is provided to bias clutch C1 out of engagement.
  • the clutch piston 66, as well as the pressure operated elements of the other clutches and brakes, are each provided with hydraulic fluid from a pump (not shown) under the control of a corresponding one of the valves 22, in the usual fashion which is well-known to one of ordinary skill in the art, and therefore will not be described further herein.
  • a pump not shown
  • the circuit shown in FIGS. 4b-4f functions to provide one forward and one reverse gear if a failure occurs in a component resulting in loss of normal transmission operation.
  • This circuit includes a first pair of mating 10-terminal connectors J1, J2 and a second pair of mating 10-terminal connectors J3, J4, a limp-home relay K22, and a "clutch disengaged" switch S4.
  • connectors J1 and J2 are mated together and connector J4 is covered with connector J3 which functions as a dust cap.
  • Line V+ also supplies power to the common terminals of not neutral switch S1, forward switch S2 and reverse switch S3.
  • Switch S1, and directional switches S2 and S3 are operatively coupled to the shift lever 36.
  • switch S1 When lever 36 is in its neutral position switch S1 connects power to neutral line 72, and when lever 36 is not in its neutral position switch S1 connects power to not-neutral line 74.
  • Switch S2 connects power to forward line L2 when lever 36 is in a forward gear position and disconnects line L2 from the power when lever 36 is not a forward gear position.
  • Switch S3 connects power to reverse line L3 when lever 36 is in a reverse gear position and disconnects line L3 from the power when lever 36 is not in a reverse gear position.
  • Line 72 is connected to one side of the coil of SIG latching relay K20.
  • Latching relay K20 has a pin 30 connected to line 70 and a pin 87 connected to line 72 and to one side of the coil of SIG enabling relay K21.
  • the other side of the coil of relay K20 is connected to the starter solenoid 76 via line 78 and diode D1.
  • Pin 30 of SIG enabling relay K21 is connected to line 74 and pin 87 is connected to not neutral line L1.
  • a clutch disengaged switch S4 is connected between line L1 and pin 85 and one side of the coil of limp-home relay K22.
  • Relay K22 has a pin 30 connected to pin C of connector J4, a pin 87 connected to pin 85 and to pins G and H of connector J4.
  • Connector J1 has a pin SG connected to line 70, a pin V+connected to line V+, a pin NN connected to line L1, a pin F connected to line L2, a pin R connected to line L3, a pin LS connected to a tachometer (not shown), a pin C2 connected to clutch control valve C2, a pin B1 connected to clutch control valve B1, a pin B5 connected to clutch control valve B5, and a pin B4 connected to clutch control valve B4.
  • Connector J2 has pins A and B connected together and to the controller power supply, pins C, D and E connected to the microprocessor 82, unconnected pin F and pins G, H, J and K connected to the drivers 24 for control valves C2, B1, B5 and B4, respectively.
  • Connector J3 merely serves as a dust cap for connector J4.
  • Pins A, B and F of connector J4 are jumpered together, as are pins D and J and pins E and K.
  • Pin C of connector J4 is connected to pin 30 of relay K22, and pins G and H of connector J4 is connected to pins 87 and 85 of relay K22.
  • switch S1 and the start-in-gear relays K20 and K21 will prevent power from reaching the non-neutral line L1 which supplies power to the B1 and C2 transmission element control valves. This is because when the transmission lever 36 is in gear, switch S1 disconnects line 72 neutral from power, and the relays K20 and K21 will remain off. Since switch S1 disconnects line 72, there is no way to energize relays K20 and K21. So, if the engine is started in this condition, the B1 and C2 control valves will not be energized and the transmission 18 will not be carrying torque.
  • the shift lever 36 To actually engage a gear, the shift lever 36 must be moved to its neutral position so that switch S1 energizes line 72. This applies power through line 72 to the coil of relay K20 so that relay K20 closes its contacts and supplies power through that contact to its own coil and also to the coil of K21. So, now that K20 and K21 are both energized and K20 is latched, the shift lever 36 is moved into a gear position so that switch S1 energizes line 74.
  • the closed contacts of relay K21 pass power from V+via line 74 to line L1, to the clutch disengaged switch S4, and also to pin C of connector J2 which supplies signal L1 to the transmission control unit 30 and thus to six of the valve drivers 24. With this signal to the valve drivers 24 completed, the control unit 30 will be able to provide gear engagement in accordance with the motion of shift lever 36.
  • the circuit of the present invention will stop gear engagement if the engine 10 is started by shorting across the terminals of the starter solenoid 76. This is because the start-in-gear circuit will shut off power to the drivers for solenoids C1, C2, B1, and B2. Power to the clutch cooling and input planetary valve drivers is also shut off, but these are not required for gear engagement.
  • the circuit provides for two limp-home gears when J1 is connected to J4.
  • Gear 9F is the forward gear and gear 4R is the reverse gear.
  • the selected gear is determined by whether the forward switch S2 is closed, or whether the reverse switch S3 is closed.
  • To activate gear 9F the valves 22 for transmission control clutches B1, C2 and B5 must be energized.
  • gear 4R To activate gear 4R the valves 22 for transmission control clutches B1, C2 and B4 must be energized.
  • the two gears have transmission elements B1 and C2 in common, and for either gear, all three elements must be on in order for power to be transmitted through the transmission 18.
  • the engine 10 will be turned on with shift lever 36 in neutral. Then, as soon as the key switch S5 is released, the relay K20 is energized by line 72 from switch S1. The closure of the contact of relay K20 keeps K20 energized, and thus relay K21 is also energized. This enables power to certain of the transmission solenoid valves 22 through relay K21 when switch S1 switches to "not neutral" when the shift lever 36 is moved to a forward or reverse gear position. Since the shift lever is in neutral, line L1 will be de-energized, and therefore relay K22 will be de-energized.
  • K22 is de-energized because switch S1 opens.
  • switch S1 opens.
  • the operator will again have to manipulate the shift lever 36 and depress and release the clutch pedal 44 as described in the preceding paragraph.
  • the reason for relay K22 is to make sure the operator is in control of the vehicle when shifting into a limp-home gear.
  • a 12 volt (nominal) signal is sent to the dashboard display 34 whenever the key switch S5 is on ("run" position) and J1 is connected to J4. Power for this signal comes from J1 pin B and is routed to J1 pin F by the jumper wire between J4 pin B and J4 pin F. This signal activates a gear symbol annunciator on the dashboard display 34.
  • This limp-home circuit is specifically intended for use by the operator when it is important to continue working with the tractor. Because of this, the shift lever switches S1, S2 and S3 must be functional, relays K20, K21 and K22, and clutch disengaged switch S4 must be functional. These components provide the necessary protection against unexpected motion as well as allowing the operator to use the normal controls for operating the transmission.
  • the gear encoder 82 provides information to the transmission controller 30 to indicate the position of the shift lever 36.
  • the transmission controller 30 will not allow gear engagement if the gear encoder 82 is not working. Wheel speed information is important to normal operation of the transmission controller 30. If the engine 10 is running and the transmission 18 is in gear and the clutch (not shown) is fully engaged, then the tractor should be moving. If the transmission controller 30 is not receiving wheel speed information, then the transmission controller 30 must command neutral in case a problem actually exists where unexpected motion may occur.
  • the limp-home function of the present invention allows the operator to modulate the engagement into a gear with the clutch pedal 44 because the clutch (not shown) has a mechanical linkage (not shown) to a hydraulic valve (not shown) in the transmission 18. Therefore an electronic failure in the system does not affect the operation of the clutch pedal 44.
  • the circuit of the present invention will also prevent gear engagement if the engine 10 is started by shorting across the terminals of the starter solenoid 76, because the start-in-gear circuit will shut off power to the B1 and C2 solenoid valves if the engine 10 is started, thus preventing gear engagement.
  • the ground circuit for latching relay K20 includes the low resistance coil of the starter solenoid 76, so when battery voltage is applied to the ST terminal of the starter solenoid 76, the series diode D1 is reversed biased and there is no longer a ground path through the coil of relay K20 and the relay K20 de-energizes.
  • the diode D1 also prevents power at the starter solenoid 76 from energizing the series combination of K20 and K21 when the shift lever 36 is not in neutral.
  • relay K20 When relay K20 is de-energized with the shift lever 36 in gear, the relay contact is open and the not neutral switch S1 is connected to terminal A of the switch module connector. Therefore, there is no longer any voltage to keep enabling relay K21 energized. If K21 is de-energized, the not neutral line L1 is dead and power cannot be applied to valves B1 and C2.

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  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Control Of Transmission Device (AREA)
  • Arrangement And Mounting Of Devices That Control Transmission Of Motive Force (AREA)
US07/923,701 1992-07-31 1992-07-31 Transmission control with limp-home function Expired - Lifetime US5251733A (en)

Priority Applications (5)

Application Number Priority Date Filing Date Title
US07/923,701 US5251733A (en) 1992-07-31 1992-07-31 Transmission control with limp-home function
CA002099156A CA2099156C (en) 1992-07-31 1993-06-25 Transmission control with limp-home function
JP16691093A JP3502416B2 (ja) 1992-07-31 1993-07-06 リンプ・ホーム機能を備えたトランスミッション制御システム
EP93111339A EP0581124B1 (de) 1992-07-31 1993-07-15 Getriebesteuerung mit Notbetriebsfunktion
DE59307449T DE59307449D1 (de) 1992-07-31 1993-07-15 Getriebesteuerung mit Notbetriebsfunktion

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US07/923,701 US5251733A (en) 1992-07-31 1992-07-31 Transmission control with limp-home function

Publications (1)

Publication Number Publication Date
US5251733A true US5251733A (en) 1993-10-12

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Application Number Title Priority Date Filing Date
US07/923,701 Expired - Lifetime US5251733A (en) 1992-07-31 1992-07-31 Transmission control with limp-home function

Country Status (5)

Country Link
US (1) US5251733A (ja)
EP (1) EP0581124B1 (ja)
JP (1) JP3502416B2 (ja)
CA (1) CA2099156C (ja)
DE (1) DE59307449D1 (ja)

Cited By (27)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5438887A (en) * 1993-11-22 1995-08-08 Caterpillar Inc. Electro-hydraulic interlock system for a transmission
EP0754885A2 (de) 1993-12-01 1997-01-22 Deere & Company Getriebeschalthebelanordnung
US5778330A (en) * 1995-10-19 1998-07-07 Case Corporation Microprocessor controlled neutral circuit for a power transmission
US5790969A (en) * 1996-01-03 1998-08-04 Case Corporation Switch activated limp-home circuit for a power transmission
US5809441A (en) * 1995-10-19 1998-09-15 Case Corporation Apparatus and method of neutral start control of a power transmission
US5957806A (en) * 1996-06-04 1999-09-28 Mitsubishi Jidosha Kogyo Kabushiki Kaisha Apparatus and method for disengaging a clutch after a shift command unless a clutch pedal is in a clutch slipping state
US6129187A (en) * 1996-11-15 2000-10-10 Agco Sa PTO shaft monitoring and control system
GB2355502A (en) * 1999-10-20 2001-04-25 Luk Lamellen & Kupplungsbau Transmission controller that automatically disengages a selected gear if a vehicle does not move away
US6488609B1 (en) * 1999-09-30 2002-12-03 Suzuki Motor Corporation Motor control apparatus combined to engine
US20030022749A1 (en) * 2001-07-25 2003-01-30 Aisin Aw Co., Ltd. Automatic transmission with a hydraulic control apparatus
EP1293375A1 (fr) * 2001-09-14 2003-03-19 Renault s.a.s. Procédé de commande des électrovannes de selection et d'embrayage d'une transmission automatisée
US6633805B2 (en) 2001-07-13 2003-10-14 Deere & Company Control system for reverser transmission having aggressive and non-aggressive modes
EP1057686A3 (de) * 1999-06-05 2004-01-14 WABCO GmbH & CO. OHG Gangschaltung für Kraftfahrzeuge
US6851495B2 (en) 2001-10-19 2005-02-08 Deere & Co. Speed control for utility vehicle operable from rearward-facing seat
US20070078042A1 (en) * 2005-09-30 2007-04-05 Jatco Ltd Automatic transmission
WO2008026993A1 (en) * 2006-09-01 2008-03-06 Scania Cv Ab (Publ) A method for shifting gear in a gear-by-wire system in a vehicle, a vehicle equipped with a clutch, a computer program adapted for shifting gear in a gear-by-wire system in a vehicle and an electronic control unit
US20080221764A1 (en) * 2007-03-09 2008-09-11 Jatco Ltd Automatic transmission and control method thereof
DE10036601B4 (de) * 2000-07-27 2009-01-15 Daimler Ag Vorrichtung zur Steuerung eines Kraftfahrzeuggetriebes
CN103277502A (zh) * 2013-06-24 2013-09-04 广西柳工机械股份有限公司 装载机变速控制系统
CN108980338A (zh) * 2018-08-14 2018-12-11 吉利汽车研究院（宁波）有限公司 电子离合器及车辆
CN109307068A (zh) * 2018-11-23 2019-02-05 广州汽车集团股份有限公司 手自一体自动变速器的液压系统
JP2019213501A (ja) * 2018-06-13 2019-12-19 株式会社クボタ 収穫機の走行制御装置
US11054020B2 (en) 2016-12-22 2021-07-06 Eaton Cummins Automated Transmission Technologies, Llc High efficiency, high output transmission
US11105412B2 (en) 2016-12-22 2021-08-31 Eaton Cummins Automated Transmission Technologies Llc System, method, and apparatus for managing transmission shutdown operations
CN113738864A (zh) * 2021-09-29 2021-12-03 蜂巢传动科技河北有限公司 At变速器控制方法、系统及at变速器和车辆
CN114321351A (zh) * 2021-11-08 2022-04-12 陕西法士特齿轮有限责任公司 一种液力自动变速器跛行手动阀
US11391352B2 (en) 2016-12-22 2022-07-19 Eaton Cummins Automated Transmission Technologies, Llc High efficiency, high output transmission

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4431073A1 (de) 1994-09-01 1996-03-07 Zahnradfabrik Friedrichshafen Automatgetriebe mit Notlauf
DE10234083B4 (de) * 2002-07-26 2010-06-17 GM Global Technology Operations, Inc., Detroit Starteinrichtung für ein Kraftfahrzeug
KR101220343B1 (ko) * 2006-03-16 2013-01-09 기아자동차주식회사 디젤 차량의 공연비 제한 보정장치 및 방법
CN102705505A (zh) * 2012-06-19 2012-10-03 中联重科股份有限公司 工程车辆控制设备、控制方法及工程车辆
CN106246897A (zh) * 2016-08-04 2016-12-21 武汉艾雪科技有限公司 一种基于工程技术的设备车辆控制装置

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4855913A (en) * 1987-05-29 1989-08-08 J. I. Case Company Electronic control system for powershift transmission
USRE34064E (en) * 1987-07-16 1992-09-15 Automotive Products (Usa) Inc. Electric shift apparatus

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
BR8707683A (pt) * 1986-05-02 1989-08-15 Zahnradfabrik Friedrichshafen Comando eletro-hidraulico
US4871048A (en) * 1987-09-21 1989-10-03 Dresser Industries, Inc. Control system for vehicle transmissions
DE3836421C2 (de) * 1987-11-06 1998-01-29 Volkswagen Ag Elektrohydraulische Steuereinrichtung für ein automatisches Schaltgetriebe
DE4110206A1 (de) * 1991-03-28 1992-10-01 Fendt & Co Xaver Hilfskraftbetaetigte gangschalteinrichtung

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4855913A (en) * 1987-05-29 1989-08-08 J. I. Case Company Electronic control system for powershift transmission
USRE34064E (en) * 1987-07-16 1992-09-15 Automotive Products (Usa) Inc. Electric shift apparatus

Non-Patent Citations (8)

* Cited by examiner, † Cited by third party
Title
Deere & Company, "8560, 8760 and 8960 Schematic, Chart No. 5, RW19653", (not published).
Deere & Company, "8560, 8760 and 8960 Tractors Operation and Tests, Technical Manual", Mar. 1992, p. 240-50-17.
Deere & Company, 8560, 8760 and 8960 Schematic, Chart No. 5, RW19653 , (not published). *
Deere & Company, 8560, 8760 and 8960 Tractors Operation and Tests, Technical Manual , Mar. 1992, p. 240 50 17. *
Ford New Holland, "Part 5-Transmission System", 1990, Chapters 5 and 6.
Ford New Holland, "Powershift Transmission Main Wiring Diagram", 1990.
Ford New Holland, Part 5 Transmission System , 1990, Chapters 5 and 6. *
Ford New Holland, Powershift Transmission Main Wiring Diagram , 1990. *

Cited By (49)

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Publication number Priority date Publication date Assignee Title
US5438887A (en) * 1993-11-22 1995-08-08 Caterpillar Inc. Electro-hydraulic interlock system for a transmission
EP0754885A2 (de) 1993-12-01 1997-01-22 Deere & Company Getriebeschalthebelanordnung
EP0754886A2 (de) 1993-12-01 1997-01-22 Deere & Company Getriebeschalthebelanordnung
US5778330A (en) * 1995-10-19 1998-07-07 Case Corporation Microprocessor controlled neutral circuit for a power transmission
US5809441A (en) * 1995-10-19 1998-09-15 Case Corporation Apparatus and method of neutral start control of a power transmission
US5790969A (en) * 1996-01-03 1998-08-04 Case Corporation Switch activated limp-home circuit for a power transmission
US5957806A (en) * 1996-06-04 1999-09-28 Mitsubishi Jidosha Kogyo Kabushiki Kaisha Apparatus and method for disengaging a clutch after a shift command unless a clutch pedal is in a clutch slipping state
US6129187A (en) * 1996-11-15 2000-10-10 Agco Sa PTO shaft monitoring and control system
EP1057686A3 (de) * 1999-06-05 2004-01-14 WABCO GmbH & CO. OHG Gangschaltung für Kraftfahrzeuge
US6488609B1 (en) * 1999-09-30 2002-12-03 Suzuki Motor Corporation Motor control apparatus combined to engine
GB2355502A (en) * 1999-10-20 2001-04-25 Luk Lamellen & Kupplungsbau Transmission controller that automatically disengages a selected gear if a vehicle does not move away
DE10036601B4 (de) * 2000-07-27 2009-01-15 Daimler Ag Vorrichtung zur Steuerung eines Kraftfahrzeuggetriebes
US6633805B2 (en) 2001-07-13 2003-10-14 Deere & Company Control system for reverser transmission having aggressive and non-aggressive modes
US20030022749A1 (en) * 2001-07-25 2003-01-30 Aisin Aw Co., Ltd. Automatic transmission with a hydraulic control apparatus
US6835152B2 (en) * 2001-07-25 2004-12-28 Aisin Aw Co., Ltd. Automatic transmission with a hydraulic control apparatus
FR2829822A1 (fr) * 2001-09-14 2003-03-21 Renault Procede de commande des electrovannes d'une transmission automatisee
EP1293375A1 (fr) * 2001-09-14 2003-03-19 Renault s.a.s. Procédé de commande des électrovannes de selection et d'embrayage d'une transmission automatisée
US6851495B2 (en) 2001-10-19 2005-02-08 Deere & Co. Speed control for utility vehicle operable from rearward-facing seat
US20070078042A1 (en) * 2005-09-30 2007-04-05 Jatco Ltd Automatic transmission
US7513850B2 (en) * 2005-09-30 2009-04-07 Jatco Ltd Automatic transmission
WO2008026993A1 (en) * 2006-09-01 2008-03-06 Scania Cv Ab (Publ) A method for shifting gear in a gear-by-wire system in a vehicle, a vehicle equipped with a clutch, a computer program adapted for shifting gear in a gear-by-wire system in a vehicle and an electronic control unit
DE112007002059B4 (de) 2006-09-01 2022-09-29 Scania Cv Ab (Publ) Gangschaltverfahren bei einem elektronischen Getriebesystem in einem Fahrzeug, ein mit einer Kupplung versehenes Fahrzeug, ein Computerprogramm, das dazu ausgelegt ist, bei einem elektronischen Getriebesystem in einem Fahrzeug zu schalten, und eine elektronische Steuereinheit
DE112007002059T5 (de) 2006-09-01 2009-07-09 Scania Cv Ab (Publ) Gangschaltverfahren bei einem elektronischen Getriebesystem in einem Fahrzeug, ein mit einer Kupplung versehenes Fahrzeug, ein Computerprogramm, das dazu ausgelegt ist, bei einem elektronischen Getriebesystem in einem Fahrzeug zu schalten, und eine elektronische Steuereinheit
US20080221764A1 (en) * 2007-03-09 2008-09-11 Jatco Ltd Automatic transmission and control method thereof
US8224542B2 (en) * 2007-03-09 2012-07-17 Jatco Ltd Automatic transmission and control method thereof
CN103277502A (zh) * 2013-06-24 2013-09-04 广西柳工机械股份有限公司 装载机变速控制系统
CN103277502B (zh) * 2013-06-24 2015-07-22 广西柳工机械股份有限公司 装载机变速控制系统
US11320044B2 (en) 2016-12-22 2022-05-03 Eaton Cummins Automated Transmission Technologies, Llc Pneumatic transmission control
US11441671B2 (en) 2016-12-22 2022-09-13 Eaton Cummins Automated Transmission Technologies, Llc High efficiency, high output transmission having an aluminum housing
US11391352B2 (en) 2016-12-22 2022-07-19 Eaton Cummins Automated Transmission Technologies, Llc High efficiency, high output transmission
US11105412B2 (en) 2016-12-22 2021-08-31 Eaton Cummins Automated Transmission Technologies Llc System, method, and apparatus for managing transmission shutdown operations
US11118672B2 (en) * 2016-12-22 2021-09-14 Eaton Cummins Automated Transmission Technologies, Llc Pneumatic transmission control
US11346441B2 (en) 2016-12-22 2022-05-31 Eaton Cummins Automated Transmission Technologies, Llc High efficiency high output transmission with linear clutch actuator and system, method, and apparatus for control
US11499612B2 (en) 2016-12-22 2022-11-15 Eaton Cummins Automated Transmission Technologies, Llc High efficiency, high output transmission having ease of integration features
US11313456B2 (en) * 2016-12-22 2022-04-26 Eaton Cummins Automated Transmission Technologies, Llc Clutch control for a high efficiency, high output transmission having improved response and position control
US11408502B2 (en) 2016-12-22 2022-08-09 Eaton Cummins Automated Transmission Technologies Llc System, method, and apparatus for managing transmission shutdown operations
US11493125B2 (en) 2016-12-22 2022-11-08 Eaton Cummins Automated Transmission Technologies, Llc High efficiency, high output transmission
US12000465B2 (en) 2016-12-22 2024-06-04 Eaton Cummins Automated Transmission Technologies Llc High efficiency, high output transmission having ease of integration features
US11054020B2 (en) 2016-12-22 2021-07-06 Eaton Cummins Automated Transmission Technologies, Llc High efficiency, high output transmission
US11320043B2 (en) 2016-12-22 2022-05-03 Eaton Cummins Automated Transmission Technologies, Llc Coolerless high efficiency, high output transmission
US11592090B2 (en) 2016-12-22 2023-02-28 Eaton Cummins Automated Transmission Technologies Llc High efficiency, high output transmission having ease of integration features
US11441651B2 (en) 2016-12-22 2022-09-13 Eaton Cummins Automated Transmission Technologies, Llc High efficiency, high output transmission having improvements to support bearing reliability and efficiency
JP2019213501A (ja) * 2018-06-13 2019-12-19 株式会社クボタ 収穫機の走行制御装置
CN108980338A (zh) * 2018-08-14 2018-12-11 吉利汽车研究院（宁波）有限公司 电子离合器及车辆
CN109307068A (zh) * 2018-11-23 2019-02-05 广州汽车集团股份有限公司 手自一体自动变速器的液压系统
CN109307068B (zh) * 2018-11-23 2023-10-03 广州汽车集团股份有限公司 手自一体自动变速器的液压系统
CN113738864B (zh) * 2021-09-29 2022-10-28 蜂巢传动科技河北有限公司 At变速器控制方法、系统及at变速器和车辆
CN113738864A (zh) * 2021-09-29 2021-12-03 蜂巢传动科技河北有限公司 At变速器控制方法、系统及at变速器和车辆
CN114321351A (zh) * 2021-11-08 2022-04-12 陕西法士特齿轮有限责任公司 一种液力自动变速器跛行手动阀

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CA2099156A1 (en) 1994-02-01
EP0581124B1 (de) 1997-10-01
CA2099156C (en) 1998-10-20
DE59307449D1 (de) 1997-11-06
EP0581124A3 (en) 1996-03-06
EP0581124A2 (de) 1994-02-02
JPH06174070A (ja) 1994-06-21
JP3502416B2 (ja) 2004-03-02

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